Giải pt: \(3x^2-10x+6+\left(x+2\right)\sqrt{2-x^2}=0\)
Giải pt : a) \(8x^2-13x+7=\left(1+\frac{1}{x}\right)\sqrt[3]{3x^2-2}\)
b) \(\sqrt{4x^2+5x+1}-2\sqrt{x^2-x+1}=9x-3\)
c) \(2\sqrt{x+1}+6\sqrt{9-x^2}+6\sqrt{\left(x+1\right)\left(9-x^2\right)}=38+10x-2x^2-x^3\)
Vũ Minh Tuấn, Băng Băng 2k6, Hoàng Tử Hà, đề bài khó wá, Lê Gia Bảo, Aki Tsuki, Nguyễn Việt Lâm,
Lê Thị Thục Hiền, Nguyễn Trúc Giang, Học 24h, @tth_new, @Akai Haruma
Help me! Cần gấp
thanks!
giải pt :
a, \(\sqrt[3]{2-x}=1-\sqrt{x-1}\)
b, \(2\sqrt[3]{3x-2}+3\sqrt{6-5x}-8=0\)
c, \(\left(x+3\right)\sqrt{-x^2-8x+48}=x-24\)
d, \(\sqrt[3]{\left(2-x\right)^2}+\sqrt[3]{\left(7+x\right)\left(2-x\right)}=3\)
e, \(\dfrac{\sqrt[3]{7-x}-\sqrt[3]{x-5}}{\sqrt[3]{7-x}+\sqrt[3]{x-5}}=6-x\)
Giải pt, bất pt
a) \(\left(\sqrt{x+3}-\sqrt{x+1}\right)\left(x^2+\sqrt{x^2+4x+3}=2x\right)\)
b) \(\left(x^2-3x+2\right)\left(x^2-12x+32\right)\le4x^2\)
c) \(2\sqrt{3x+7}-5\sqrt[3]{x-6}=4\)
1) giải pt \(-3x^2+x+3+\left(\sqrt{3x+2}-4\right)\sqrt{3x-2x^2}+\left(x+1\right)\sqrt{3x+2}=0\)
Cho \(f\left(x\right)=\left(x-2\right)\left(\sqrt{3x^2+1}\right)\). giải pt f(x)' \(^2\) =0?
Đề là \(f''\left(x\right)=0\) hay \(\left[f'\left(x\right)\right]^2=0\) nhỉ?
\(f'\left(x\right)=\sqrt{3x^2+1}+\dfrac{3x\left(x-2\right)}{\sqrt{3x^2+1}}=\dfrac{6x^2-6x+1}{\sqrt{3x^2+1}}\)
\(\left[f'\left(x\right)\right]^2=0\Leftrightarrow f'\left(x\right)=0\Leftrightarrow6x^2-6x+1=0\)
\(\Rightarrow x=\dfrac{3\pm\sqrt{3}}{6}\)
Giải PT. \(10x^2+3x+1=\left(6x+1\right)\sqrt{x^2+3}\)
Đặt \(t=6x+1\)và \(h=\sqrt{x^2+3}\)
\(\frac{1}{4}\cdot t^2+h^2-\frac{9}{4}=th\)
\(\Leftrightarrow\left(t-2h\right)^2=9\)
\(\Leftrightarrow t-2h=\pm3\)
Với \(t-2h=3\)ta có
\(6x+1-2\sqrt{x^2+3}=3\)
\(\Leftrightarrow3x-1=\sqrt{x^2+3}\)
\(\Leftrightarrow\hept{\begin{cases}3x-1\ge0\\x^2+3=\left(3x+2\right)^2\end{cases}\Leftrightarrow x=\frac{\sqrt{7}-3}{4}}\)
Vậy pt có nghiệm là \(x=1;x=\frac{\sqrt{7}-3}{4}\)
giải pt
a) \(\sqrt{4x^2-12x+9}=\left|3x-2\right|\)
b) \(\sqrt{25x^2-10x+1}=\left|x+6\right|\)
c) \(\sqrt{16x^2-8x+1}=\left|x-3\right|\)
d) \(\left|5x+1\right|=2x-3\)
e) \(\left|3x-4\right|=\left|x-2\right|\)
f) \(\left|3x^2-2x\right|=\left|6-x^2\right|\)
g) \(\left|x^2-2x\right|=\left|2x^2-x-2\right|\)
a/
\(\Leftrightarrow4x^2-12x+9=\left(3x-2\right)^2\)
\(\Leftrightarrow5x^2-5=0\Rightarrow x=\pm1\)
b/
\(\Leftrightarrow25x^2-10x+1=\left(x+6\right)^2\)
\(\Leftrightarrow24x^2-22x-35=0\Rightarrow\left[{}\begin{matrix}x=\frac{7}{4}\\x=-\frac{5}{6}\end{matrix}\right.\)
c/
\(\Leftrightarrow16x^2-8x+1=\left(x-3\right)^2\)
\(\Leftrightarrow15x^2-2x-8=0\Rightarrow\left[{}\begin{matrix}x=\frac{4}{5}\\x=-\frac{2}{3}\end{matrix}\right.\)
d/ \(x\ge\frac{3}{2}\)
\(\Leftrightarrow\left(5x+1\right)^2=\left(2x-3\right)^2\)
\(\Leftrightarrow21x^2+22x-8=0\Rightarrow\left[{}\begin{matrix}x=\frac{2}{7}\\x=-\frac{4}{3}\end{matrix}\right.\)
e/
\(\Leftrightarrow\left[{}\begin{matrix}3x-4=x-2\\3x-4=2-x\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}2x=2\\4x=6\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=1\\x=\frac{3}{2}\end{matrix}\right.\)
f/
\(\Leftrightarrow\left[{}\begin{matrix}3x^2-2x=6-x^2\\3x^2-2x=x^2-6\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}4x^2-2x-6=0\\2x^2-2x+6=0\left(vn\right)\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=-1\\x=\frac{3}{2}\end{matrix}\right.\)
g/
\(\Leftrightarrow\left[{}\begin{matrix}x^2-2x=2x^2-x-2\\x^2-2x=-2x^2+x+2\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x^2+x-2=0\\3x^2-3x-2=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=1\\x=-2\\x=\frac{3\pm\sqrt{33}}{6}\\\end{matrix}\right.\)
Giải pt và hệ pt:
a)\(\sqrt{5x+1}-\sqrt{4-x}+2x^2-5x+6=0\)
b)\(\left\{{}\begin{matrix}\sqrt{2x+1}+\sqrt{2y+1}=\frac{\left(x-y\right)^2}{2}\\\left(x+y\right)\left(x+2y\right)+3x+2y=4\end{matrix}\right.\)
Giải pt \(6x^2+10x+11-3\left(2x+3\right)\sqrt{x^2-x+1}=0\)
Đặt \(\left\{{}\begin{matrix}2x+3=a\\\sqrt{x^2-x+1}=b>0\end{matrix}\right.\)
Pt trở thành:
\(a^2+2b^2-3ab=0\)
\(\Leftrightarrow\left[{}\begin{matrix}a=b\\a=2b\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x^2-x+1}=2x+3\\2\sqrt{x^2-x+1}=2x+3\end{matrix}\right.\)
\(\Leftrightarrow...\)